1. Technical Field
The present disclosure relates to a quadrature radar apparatus, and more particularly, to a quadrature radar apparatus having a transmission leakage signal canceller, which can reduce a polarization loss and an interference between radars.
2. Related Art
Researches relating to a radar apparatus have been made, as disclosed in, e.g., Korean Patent No. 0748992 entitled “circular polarization radar apparatus.”
As described in FIG. 1, this disclosure relates to a circular polarization radar apparatus of obtaining a base band signal by removing a transmission leakage signal without a loss of transmission power. The apparatus includes: a signal generator 11 generating two signals having 180 degrees of the phase difference; first and second coupler modules 12 and 13 each receiving each of the two signals generated from the signal generator; a circular polarization type antenna 14 receiving signals from the first and second coupler modules; a 90 degree phase delay module 15 connected between the second coupler module and an input of the antenna; a power combining unit 16 combining a reception signal inputted from the antenna and removing reception signals leaked from the first and second coupler modules; and a mixer 17 mixing the signals from the first and second coupler modules and the signal from the power combining unit.
According to the related art technology as described above, however, there is a limitation in that a loss of 3 db signal on a signal generator may occur upon reception.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.